Description
Johann Carl Friedrich Gauß (1777 – 1855) was one of the most important German mathematicians. For those of you who remember the Deutsche Mark, a picture of him was printed on the 10 – DM bill. In elementary school, his teacher J. G. Büttner tried to occupy the pupils by making them add up the integers from 1 to 100. The young Gauß surprised everybody by producing the correct answers (5050) within seconds.
Can you write a computer program that can compute such sums really quickly?
Given two integers n and m, you should compute the sum of all the integers from n to m. In other words, you should compute
Input
The first line contains the number of scenarios. Each scenario consists of a line containing the numbers n and m (−109 ≤ n ≤ m ≤ 109).
Output
The output for every scenario begins with a line containing “Scenario #i:”, where i is the number of the scenario starting at 1. Then print the sum of all integers from n to m. Terminate the output for the scenario with a blank line.
Sample Input
3 1 100 -11 10 -89173 938749341Sample Output
Scenario #1: 5050 Scenario #2: -11 Scenario #3: 440625159107385260 #include <iostream>using namespace std;int main (){int set,i; __int64 n,m; scanf("%d", &set);for(i=1;i<=set;i++) { scanf("%I64d %I64d",&n,&m); printf("Scenario #%d:\n",i); printf("%I64d\n\n",(n+m)*(m-n+1)/2); }return 0;}转载于:https://www.cnblogs.com/w0w0/archive/2011/11/22/2258738.html
相关资源：数据结构—成绩单生成器